OFVERIFY (Jun94) ftools.futils OFVERIFY (Jun94)
NAME
ofverify -- Verify that a FITS file conforms to the FITS Standard.
USAGE
ofverify filename
DESCRIPTION
This task reads a FITS file and verifies that the header and data in
the primary array and in every extension conform to the FITS format
standard. It first reads the required header keywords to check that
they are in the correct order and have legal values. Then all the
remaining header keywords are read to verify that they conform to
the FITS syntax rules. This includes testing for illegal
characters in the keyword names (only A-Z, 0-9, hyphen and
underscore allowed) or in the value and comment fields (any ASCII
'text' character is allowed). The value field is parsed to verify
that it is a valid FITS datatype (a quoted string, and integer, a
floating point value, or a boolean T or F value). A warning
message is printed if any duplicate keywords are found (except for
COMMENT, and HISTORY and other comment-type keywords that do not
have an '= ' in columns 9 and 10) . Finally, any fill characters
after the END keyword are checked to be sure that they are all
blanks (ASCII 32).
If the TESTDATA option is set, then OFVERIFY next attempts to read
all the data values. For primary arrays and image extensions it
computes and displays the minimum and maximum data value and also
counts the number of pixels that are undefined (i.e., are set to
the null value). For Random Group FITS files this information is
calculated for each group separately. For ASCII or binary table
extensions, each column is read individually and the minimum and
maximum values and the number of undefined values are calculated.
Ofverify supports both fixed-length and variable-length vector
columns in binary tables,
Finally, OFVERIFY checks that any fill bytes at the end of the data
have a valid value (i.e., must equal zero except for ASCII tables
which must be filled with ASCII blanks).
Every extension in the FITS file is checked in turn until the end
of file is detected.
NOTE: OFVERIFY also used to check whether there were any extraneous
bytes in the file following the last valid HDU, but this check was
disabled for technical reasons in July 2000.
OFVERIFY prints a summary table to the terminal (or to an optional
output file) showing the structure of the FITS file and a
description of any errors that it finds. Optionally, all the
header keywords may also be printed.
PARAMETERS
infile [file name]
Name of the FITS file to be verified.
outfile [file name]
Name of optional output file to write the verification report.
If outfile is blank or = 'STDOUT' then the results will be
written to the standard output device (usually the user's
terminal) rather than to a file. If preceeded by a !, an
existing file of the same name will be overwritten.
(prhead = no) [boolean]
Should the header keywords be printed to the output file?
(testdata = yes) [boolean]
Should every data value be read and verified? Turning this
option off greatly increases the execution speed of the task at
the expense of doing a less rigorous verification of the FITS
file. Only the header keywords and the data fill values will
be checked if testdata = no.
(clobber = no) [boolean]
If true, a file of the same name as the requested output file
will be overwritten.
EXAMPLES
1. Verify the contents of the FITS file 'test.fits':
ft> ofverify test.fits
2. Verify the FITS file 'test.fits' and print all the header
keywords:
ft> ofverify test.fits prhead=yes
BUGS
SEE ALSO
fstruct, flcol, fdump, fimgdmp